package com.woniuxy.userassembly.common;

public class RandomUtil {
    public static String randomStr(Integer num){
        StringBuilder sb = new StringBuilder();
        String str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        for(int i = 0;i<num;i++){
            sb.append(str.charAt((int)(Math.random()*62)));
        }
        return sb.toString();
    }
}